Memory devices are typically provided as internal, semiconductor, integrated circuits in computers or other electronic devices. There are many different types of memory including random-access memory (RAM), read only memory (ROM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), and flash memory.
Flash memory devices have developed into a popular source of non-volatile memory for a wide range of electronic applications. Flash memory devices typically use a one-transistor memory cell that allows for high memory densities, high reliability, and low power consumption. Common uses for flash memory include personal computers, personal digital assistants (PDAs), digital cameras, and cellular telephones. Program code and system data such as a basic input/output system (BIOS) are typically stored in flash memory devices for use in personal computer systems.
Block 0 of a flash memory device is typically advertised by the IC manufacturer to be a defect free block. This block can be used by electronics manufacturers to store data that cannot tolerate bit errors due to memory defects or an access disturb. For example, a computer manufacturer may use Block 0 to hold a computer's BIOS.
Block 0 is physically the same as the other blocks in the memory device; it is not made more reliable than the other blocks. This block is tested for defects at the factory during the manufacturing process. If it is determined to have a defect, that particular part has to be destroyed. This decreases the manufacturer's part yield, thus increasing costs.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a way to improve the reliability of a particular block in a memory device.